If your coffee table has a lower shelf you don’t have to fill both levels but if you choose to try lining up the items on each tier. Use two pairs instead of threes and don’t forget to play with heights. A lidded storage box or small basket can help keep the bottom level looking sharp while giving you a place to stash items like remote controls.
Coffee tables should be the same height as the surrounding seating with 18 inches being a good average (although it will depend on your furniture). If you select a coffee table with a lip make sure the lip isn’t higher than the adjacent seating or you’ll end up hitting your drink against the lip when you try to set it down. The idea is to put your drink down not up.